This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Objective: We aimed to compare concentrations of glutamatergic metabolites in bipolar offspring and healthy controls to examine whether decreases in prefrontal glutamate concentrations occur in bipolar offspringand prior to the onset of mania. Methods: 9[unreadable]18 year old children and adolescents with a familial risk for bipolar I or II disorder (22 offspring with established history of mania,"BD," and 15 with subsyndromal symptoms without mania, "SS"), and 17 healthy controls ("HC") were examined using proton magnetic resonance spectroscopy (1H-MRS) at 3T to study glutamatergic concentrations in an 8 cc (2 x 2 x 2 cm) anterior cingulate cortex (ACC) voxel. Data was processed using LCModel (Provencher, 2001).